Materials Data on Li3FeF6 by Materials Project

Abstract

Li3FeF6 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 1.95–2.04 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Li–F bond distances ranging from 1.91–2.45 Å. In the third Li1+ site, Li1+ is bonded to five F1- atoms to form LiF5 square pyramids that share corners with five FeF6 octahedra. The corner-sharing octahedra tilt angles range from 27–52°. There are a spread of Li–F bond distances ranging from 1.95–2.10 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with four equivalent LiF5 square pyramids. There is two shorter (1.93 Å) and four longer (1.98 Å) Fe–F bond length. In the second Fe3+ site, Fe3+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with six equivalent LiF5 square pyramids. There are a spread of Fe–F bond distances ranging from 1.94–1.99 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one Fe3+ atom. In the second F1- site, F1- is bonded to three Li1+ and one Fe3+ atom to form a mixture of distorted edge and corner-sharing FLi3Fe trigonal pyramids. In the third F1- site, F1- is bonded in a 3-coordinate geometry to two Li1+ and one Fe3+ atom. In the fourth F1- site, F1- is bonded to three Li1+ and one Fe3+ atom to form a mixture of distorted edge and corner-sharing FLi3Fe trigonal pyramids. In the fifth F1- site, F1- is bonded to three Li1+ and one Fe3+ atom to form a mixture of distorted edge and corner-sharing FLi3Fe trigonal pyramids. In the sixth F1- site, F1- is bonded in a 2-coordinate geometry to two equivalent Li1+ and one Fe3+ atom.